644324 has 12 divisors (see below), whose sum is σ = 1142400. Its totient is φ = 317928.

The previous prime is 644297. The next prime is 644327. The reversal of 644324 is 423446.

It is a happy number.

644324 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 644324.

It is not an unprimeable number, because it can be changed into a prime (644327) by changing a digit.

644324 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 704 + ... + 1335.

It is an arithmetic number, because the mean of its divisors is an integer number (95200).

2⁶⁴⁴³²⁴ is an apocalyptic number.

It is an amenable number.

644324 is a deficient number, since it is larger than the sum of its proper divisors (498076).

644324 is a wasteful number, since it uses less digits than its factorization.

644324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2122 (or 2120 counting only the distinct ones).

The product of its digits is 2304, while the sum is 23.

The square root of 644324 is about 802.6979506639. The cubic root of 644324 is about 86.3710308115.

The spelling of 644324 in words is "six hundred forty-four thousand, three hundred twenty-four".